Gun forearm



Dec. 27, 1960 e. c. SULLIVAN GUN FOREARM Filed May 20, 1 957 m m? M by m WM ATTORN a o 0 0 O 0 United States Patent GUN FOREARM George C. Sullivan, 3085 Lake Hollywood Drive, Hollywood 28, Calif.

Filed May 20, 1957, Ser. No. 660,103

9 Claims. (Cl. 42-71) This invention relates to an improved foreend or forearm or hand guard for a gun, more particularly for an automatic weapon.

It has been found that during extended endurance firing tests, a gun barrel can exceed 1,000 F. If equipped with the usual wood forearm, there is the danger that it could burst into flames. If equipped with a metal forearm, it would get too hot to handle. When the temperature of the forearm becomes excessive, either the rifleman cannot hold it or the heat rays given off by the forearm rise and interfere with sighting of the weapon.

Heretofore, such articles have been manufactured usually from high quality wood, mostly selected walnut. The forearms are initially roughened out on a lathe, with the cutter following a template or pattern of the desired shape. The forearm is then finished by conventional wood working and finishing techniques requiring considerable manual labor to produce an exceptionally fine forearm.

It is also known that wood will crack upon exposure to intense heat and in general will not stand up under rough handling. When a gun forearm is made out of wood, the process is both complicated and costly. In addition, the product'sufliers the drawback of having a rather high density and thus contributes materially to the weight of the gun upon which it is used. The finer quality woods are becoming somewhat scarce. Accordingly, it has become an important task to develop a proper substitute, that is easily producible from existing plentiful materials.

This invention fulfills the need that has arisen in this art by providing a novel gun forearm made of more commercially available materials such as plastic materials and especially foamed plastics.

It is, accordingly, a principal object of the present invention to provide a light weight and ruggedly constructed forearm embodying an internal low density core.

It is a further object of this invention to provide a forearm for a gun which is much lighter in weight than forearms known and used.

It is another object of this invention to provide a forearm having cooling vents.

It is a still further object of this invention to provide a forearm which possesses improved thermal insulating properties.

It is an object of this invention to provide a substantial cooling space between the inner surface of the forearm and the gun barrel.

Other objectives and features of the invention will become apparent from the following detailed description of a preferred embodiment of this invention when taken with the appended drawings, in which:

Figure 1 is a view in side elevation partly broken away showing a gun forearm constructed in accordance with the principles of this invention and mounted on a gun barrel;

Figure 2 is a view in top plan partly broken away showing the gun forearm of the present invention; and

2,965,994 Patented Dec. 27, 1960 Figure 3 is a view in cross-section of the organization portrayed in Figure 1 taken along line 33 of Figure l.

The gun forearm as illustrated in Figure 1 is made in generally the same manner as the gun stock in my issued Patent No. 2,753,642.

Referring to the figures in detail, a barrel is shown at 12. This barrel may be made of steel, aluminum or aluminum-steel laminated construction.

Suitable end fittings 31 and 32 hold barrel 12 in place within gun forearm 13. End fitting 31 is an annular spacer member which has radial grooves 23 that extend in an axial direction through member 31 providing spaced projections 22 which locate the barrel 12 within forearm 13 thus providing an annular cooling chamber or space 16 for the circulation of cooling air for the barrel. Member 32 serves as a reinforcing end member for the end of forearm 13 nearest the action (not shown), and is formed with means 33 to mount the end of the forearm on the action of the gun. End fittings 31 and 32 may be of any suitable material but preferably are formed of fiber glass reinforced molded phenolic resin.

Thus in operation, air may enter apertures 23 in member 31 and circulate around barrel l2 and leave the cooling chamber 16 by any of the vents 11, which are provided in an axial direction on the top and bottom of forearm 13. Cooling air may also enter through the lower vents 11. The inner wall of cooling space 16 is defined on the inside by barrel 12 and the outer wall is defined by reflection foil 14. Reflection foil 14, which is preferably about .003 inch thickness of metal foil reflects heat given off by barrel 12 into cooling chamber 16, so that forearm 13 may absorb as little heat as possible. Foil 14 forms the inside surface of the body of forearm 13.

The body of forearm 13 is made of laminated sandwich construction. The outer surface of the body of the forearm 13 is preferably formed by fiber glass molded skin 15 for reinforcing of the structure or for greater strength. Positioned between reflector foil 14 and fiber glass skin 15, is a layer 10 of isocyanate foam for the purpose of thermal insulation. End members 31 and 32 are secured in place and with the laminated sleeve construction form an integral structure. The gun forearm is molded with corrugations 17. corrugations 17 add strength to the forearm and at the same time provide an excellent grip for holding a gun steady while firing.

has been used successfully, it is to be understood that whenever throughout this specification, reference is made to foam plastic or the like, I refer not only to that specific material but to such other materials as may be cellular expanded and yet result in similar qualities.

The use of a foam plastic is particularly advantageous in this application because of its inherent property of being castable in place. The core can be foamed in situ and adhere and bond itself to an exterior skin and surround and adhere to the inner foil layer, thus producing a tough, heat resisting non-porous product.

The physical strength characteristics of the articles of this invention, in its preferred embodiment, are increased considerbly by the fact that the skins and core material are firmly bonded or joined at the interfaces.

What is claimed is:

l. A forearm for mounting on and surrounding a gun barrel comprising an annular member consisting of a laminated construction having inner and outer surface members and a low density, thermal insulating, cellular core member bonded therebetween to form an integral construction, and spacer members integrally formed at the ends of said forearm to radially space said annular member from the barrel.

While an eight pound density isocyanate foam plastic 2. A forearm for mounting on and surrounding a gun barrel comprising an annular member consisting of a laminated construction having inner and outer surface members, said inner member consisting of a metallic sheet and said outer surface member comprising fiber glass reinforced plastic, and a low density, thermal insulating, cellular core member bonded therebetween to form an integral construction, and spacer members integ'rally formed adjacent the ends of said forearm to radially space said annular member from the barrel.

3. A forearm for mounting on and surrounding a gun barrel comprising an annular sleeve member consisting of a laminated construction having a heat-reflecting inner and fiber glass reinforced outer surface members and a low density, thermal insulating, cellular core member bonded therebetween to form an integral construction, and spacer members integrally formed at the ends of said forearm to radially space said annular member from the barrel to form a cooling chamber, said sleeve member having formed therein a plurality of apertures to vent said cooling chamber.

4. A forearm for mounting on and surrounding a gun barrel comprising an annular member including core means of low density, thermal insulating, cellular material, an outer skin attached to said core means and a metal heat reflecting surface attached to the inner surface of said core means, and spacer means attached to spaced portions of said annular member to maintain said annular member radially spaced from a gun barrel when mounted thereon, said annular member and said gun barrel defining a cooling space therebetween.

5. A forearm for mounting on and surrounding a gun barrel, comprising an annular sleeve member consisting of a laminated construction having inner and outer surface members and a low density, thermal insulating, cellular core member bonded therebetween to form an integral construction, and spacer members integrally formed at the ends of said forearm to radially space said annular member from the barrel to form a cooling chamber, said sleeve member formed with a plurality of groups of vent holes for said cooling chamber and said sleeve member having a plurality of grooves extending longitudinally thereof between said groups of vent holes.

6. A forearm for mounting on and surrounding a gun barrel comprising an annular member consisting of a laminated construction having inner and fiber glass reinforcing outer surface members and a low density, thermal insulating, cellular core member bonded therebctween to form an integral construction, and spacer members integrally formed at the ends of said forearm to radially space said annular member from the barrel to form a cooling chamber.

7. A forearm for mounting on and surrounding a gun barrel, comprising an annular member including core means composed of low density, thermal insulating, cellular material, an outer skin secured to said core means, and a metal foil secured to the inner surface of said core means to form an integral laminated construction, and end fittings formed adjacent opposite ends of said annular member to maintain said annular member radially spaced from a gun barrel when mounted thereon, to define a cooling space between said annular member and said gun barrel.

8. The combination of a gun barrel and a forearm hand grip for mounting on and surrounding a gun barrel, comprising an annular member including core means composed of low density, thermal insulating, cellular material, an outer skin secured to said core means, and a metal heat reflecting surface secured to the inner surface of said core means to form an integral laminated construction, and at least one end fitting formed adjacent one end of said annular member to maintain said annular member radially spaced from said gun barrel when mounted thereon, to define a cooling space between said annular member and said gun barrel.

9. The combination of a gun barrel and a forearm hand grip for mounting on and surrounding a gun barrel, comprising an annular sleeve member including core means composed of low density, thermal insulating, cellular material, an inner and outer skin secured to said core means to form an integral laminated construction, spacer means formed adjacent opposite ends of said sleeve member to maintain said sleeve member radially spaced from said gun barrel when mounted thereon, to define a cooling space between said sleeve member and said gun barrel, and vent means formed in said sleeve member to afford cooling air access to said cooling space.

References Cited in the file of this patent UNITED STATES PATENTS 819,551 Johnson May 1, 1906 861,385 Norwood et al July 30, 1907 1,297,240 Pritchett Mar. 11, 1919 1,321,173 Wilson Nov. 11, 1919 1,357,208 Payne Oct. 26, 1920 2,674,822 Studler Apr. 13, 1954 2,753,642 Sullivan July 10, 1956 

